Device for localizing an excess in length in a thread

ABSTRACT

This device, which is adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, comprises first and second thread-guiding elements, between which is a space in which an excess in length in the thread can hang down from such elements in the form of a loop. A downward-directed nozzle is arranged adjacent to the first thread-guiding element, through which thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling. The ascending leg of the loop is relatively free of tension.

lnventor Hubert P. Van Mullekom Deurne, North Brabant, Netherlands Appl.No. 755,260 Filed Aug. 26, 1968 Patented May 25, 1971 Assignee N. V.Machinefabriek L. Te Strake Deurne, Netherlands Priority Sept. 4, 1967Netherlands 6712130 DEVICE FOR LOCALIZING AN EXCESS IN LENGTH IN ATHREAD 3 Claims, 2 Drawing Figs.

U.S. Cl 226/97, 226/113, 226/117, 226/118 Int. Cl B65h 17/32 FieldofSearch 226/7, 97,

113,118, ll7;242/182--185;28/l.4

[5 6] References Cited UNITED STATES PATENTS 2,379,824 7/1945 Mummery226/97X 2,854,059 9/1958 Palmer 226/97X 3,185,400 5/1965 Maxey 226/118X1,287,172 12/1918 Andrews..... 226/97 2,639,487 5/1953 Kelley 226/97Primary ExaminerRichard A. Schacher Attorney-Marshall and YeastingABSTRACT: This device, which is adapted to be interposed between adevice for continuously supplying a thread and a device forintermittently conveying the thread, comprises first and secondthread-guiding elements, between which is a space in which an excess inlength in the thread can hang down from such elements in the form of aloop. A downward-directed nozzle is arranged adjacent to the firstthread-guiding element, through which thread enters the loop, fordischarging fluid downward along the descending leg of the loop in orderto place the descending leg under tension so as to prevent the loop fromtangling. The ascending leg of the loop is relatively free of tension.

BACKGROUND OF THE INVENTION The invention relates to a device forlocalizing an excess in length in a thread.

In textile machinery, particularly in looms in which a thread has to beinserted into the shed by jet action the circumstances are such that athread which preferably is to be supplied from a thread package with aconstant velocity and further has to be conveyed with a variable speedbecomes periodically slack. Slackening of a running thread in textilemachinery can be very dangerous because the thread can become entangled,owing to which the thread cannot be handled anymore. It is already knownto provide an arrangement in which a thread runs in front of the mouthof a flat shaft and the excess in length in the thread can be taken upin the shape of a loop in this shaft. In such cases use is made of anairstream which runs across the path of the thread, owing to which'thethread is subjected to a strong flutter. To avoid fluttering of thethread the shaft is adapted as a guide having two opposite walls closetogether between which a loop in the thread can be guided. A furtherdrawback of such a device is the need of a relative long narrow shaft tokeep the thread tensioned in the stream of air. When a considerableexcess in length in the thread is to be localized consequently the shaftis long and it takes a considerable amount of time to remove the threadtherefrom.

SUMMARY OF THE INVENTION The object of the invention is a simple devicefor localizing an excess in length in a thread which makes possible ahigh conveying speed of the thread and in which the excess of length inthe thread can be removed at any time.

According to the invention this is attained with a device which ischaracterized by a thread supply and a thread-conveying device, betweenwhich a jet nozzle for a fluid with guiding elements for the thread hasbeen positioned in such a manner that the thread running from the supplydevice enters the path of the jet leaving the jet nozzle which thread isto be laterally drawn from the jet by means of the conveying device.

When the thread-supplying device is formed by rotating rollers drawingthe thread from a thread package only a small jet nozzle is to be placedin the path of the thread which path is located by the rollers whichconstitute a thread-guiding element, or by a thread guide proper. Thethread can be drawn laterally out of the jet at any moment and the jetnozzle can be continuously operative when the thread-removing device,such as that provided in looms e.g. a device for weft inserting is onlyperiodically operative. As the thread has already a running speed by theaction of the thread-supplying device only a small jet action of the jetnozzle will be sufficient because the jet leaving the jet nozzle neednot be used for conveying the thread.

A further advantage of the device according to the invention is thetension to which the thread between the jet nozzle and thethread-supplying device is subjected and the supplying device can besituated at a considerable distance from the device for localizing theexcess in length in the thread.

A practical embodiment according to the invention is attained in thatthe jet nozzle has been positioned with respect to a guide for thethread in such a manner that the thread leaving this guide runs parallelto the jet leaving the jet nozzle. The provision of such a guide near ajet nozzle is advantageous because the thread comes immediately incontact with the jet leaving the jet nozzle. By means of anotherthread-guiding element spaced laterally from the jet nozzle the threadcan be removed laterally from the jet.

In a device according to the invention it is advantageous that a bafflehas been situated parallel to a plane running through the jet leavingthe jet nozzle and the thread which is laterally drawn from the jet. Bythe provision of such a baffle the thread will run quietly even when alarge loop in the thread has been formed and no other air currentcreated by moving parts of the textile machinery will disturb the loopin the thread. Further it is advantageous that the baffle has beenprovided with lateral projecting sidewalls encompassing the planerunning through the jet and the thread laterally drawn from the jet,resulting in a limiting of the area in which the loop in the thread canbe formed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a diagrammaticperspective view of the device according to the invention in a firstembodiment, and

FIG. 2 shown a front view, partly in section of a device according toFIG. 1 in a second embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The device for localizing anexcess in length in a thread can be used in textile machinery in which athread periodically has an increased running speed, without subjectingthe thread to a high tension. Such circumstances occur e.g. in looms inwhich a thread is drawn from a thread package, which thread has to beinserted as a weft into the shed by jet action. When the jet leaving aweft-inserting nozzle acts on the thread this thread must not have ahigh resistance and the thread is to be supplied by a separate supplyingdevice.

When considering FIG. 1 a thread 1 is drawn from a stationary threadpackage 2. A thread eye 3 has been situated above the thread package 2,which thread eye can be fastened to a part of the textile machinery. Theprovision of a thread eye has the advantage that a thread balloon can beformed when the thread 1 is drawn from the thread package 2 at a highspeed. The thread 1 runs from the thread eye 3 to a thread guide 4. Thisthread guide 4 is positioned in front of two conical rollers 5 and 6.The thread runs over a part of the conical circumferential surface ofthe roller 5 and is pressed against same by means of a roller 6. Therollers 5 and 6 are driven e.g. by means of a separate driving mechanismor by means of a rotating shaft of a textile machine upon which thedevice according to the invention has been mounted. The position of thethread guide 4 can be adjusted in a direction parallel to the axis ofthe roller 5, owing to which the drawing speed of the thread from thethread package and further the supplying speed of the thread to theremaining part of the machinery can be accurately adjusted with a givenspeed of rotation of the roller 5 because the circumferential speed ofthat part where the thread 1 makes contact with the circumferentialsurface of the roller 5 is a measure for the running speed of thethread. Consequently a thread-supplying device is formed by the rollers5 and 6. Further the thread 1 runs to a thread-removing device whichdevice has been generally indicated by the reference numeral 7 in FIG.1.

In the embodiment shown in FIG. 1 the thread-removing device 7 isadapted as a jet nozzle for a fluid, e.g. air under pressure. The jetnozzle is connected to a source 10 of a pressure medium, preferably airby means of a line 8 and a control valve 9 (diagrammatically shown).When now the control valve is controlled e.g. by a part which rotatessynchronously with the textile machine in such a manner that at acertain moment air from the source 10 is admitted to the jet nozzle 7,the thread will be ejected from the nozzle 7 e.g. as a weft into a shed.As soon as the control valve 9 is closed the removing device for thethread, thus the jet nozzle 7, becomes inoperative whereas thethreadsupplying device formed by the rollers 5 and 6 is still operative.The result of this is an excess in length of the thread, which excesswill be received by the device according to the invention comprising ajet nozzle 11 which is directed in such a manner that the jet leavingthe nozzle I1 is directed parallel to the thread delivered by therollers 5 and 6. Preferably the thread guide 12 has been arranged nearthe jet nozzle II. The thread supplied by the rollers 5 and 6 runsthrough the thread guide 12, which thread is stretched by the jet actionof the jet nozzle 11. When now the jet nozzle 7 becomes operative thethread running through the thread eye 13 will be laterally drawn out ofthe jet leaving the jet nozzle 1 ll. The part of the thread between thethread guide 12 and the thread eye 13 is indicated in FIG. ll. The jetnozzle 11 is connected to the source for the fluid under pressure. Assoon as the jet nozzle 7 becomes operative the loop in the thread Iwhich is held in a stretched position at one side by the action of thejet nozzle III will be reduced e.g. into that state which is indicatedby the reference numeral la.

In order to prevent a fluttering of the thread e.g. caused by aircurrents created by some moving parts of the textile machinery thedevice according to the invention is provided with a baffle plate 16.Further the baffle plate possesses upright walls 170 and 17bencompassing the path of the thread between the thread eyes 12 and 13.As mentioned above the rollers 5 and 6 form the thread-supplying deviceand the jet nozzle 7 forms the thread-removing device. The design andconstruction of the thread-supplying device and the threadremovingdevice, however, are independent of the construction of the jet nozzleI 1. Instead of removing the thread by the jet action of the jet nozzle7 the thread can be removed in a mechanical manner. The main purpose ofFIG. I is to show how the excess in length in the thread between therollers 5 and 6 and the jet nozzle 7 can be localized by the action andthe arrangement of the jet nozzle 11.

In the embodiment shown in FIG. 2 a stationary thread package 2 with itsthread eye 3 has been indicated again. Further the rollers 5 and 6 fordrawing the thread 1 from the thread package are diagrammaticallyindicated. However the thread runs from the rollers 5 and 6 through apassage 18 of a ring nozzle 19. The ring nozzle 19 has been formed by achamber in a block 21. A channel 20 debouches in, the chamber of thering nozzle 19. A fluid such as air under pressure can flow through thechannel 20 to the ring nozzle 19 and a jet will leave this ring nozzlewhich jet will be formed around the thread I. As a result of theinfluence of the ring nozzle 19 secondary air stream can be created inthe passage 18 which will tension the thread leaving the rollers 5 and6. The thread 1 will be conveyed laterally of the baffle 16 to a threadeye 13a. When the rollers 5 and 6 are positioned at a considerabledistance from the ring nozzle 19 the passage 18 can be adaptedaccordingly. A channel 22 has been situated within the block 2ll abovethe baffle l6, and the channel 22 is connected to the ring nozzle 19 anddebouches through a mouth 24 near the thread eye 13a at that side of theblock where the loop in the thread is to be formed. The channel 22 hasbeen provided with an adjusting bolt 23 for choking the passage in thechannel 22. A jet can thus be created at the mouth 24 of the channel 22which jet intersects the thread near the thread eye 130. By thisarrangement the loop in the thread can be somewhat widened, owing towhich the loop in the thread can have a comparatively large length.

A good device for localizing an excess of length in a thread can beattained with very simple means as appears from the embodiments shown inthe drawing, without the need of a complicated construction. Asindicated by the shape of the loop in FIG. 2, the ascending leg of theloop, like the ascending leg of the loop in FIG. 1, is relatively freeof tension. That is true because the fluid-discharging capacity of themouth 24, because of its small size and because of the choking action ofthe adjusting bolt 23, is substantially smaller than thefluiddischarging capacity of the relatively large nozzle 19. Therelatively small stream of fluid discharged from the mouth 24 assists inkeeping the loop flat when a relatively large loop is employed.

lclaim:

l. A device for localizing an excess in length in a thread, adapted tobe interposed between a device for continuously supplying a thread and adevice for intermittently conveying the thread, wherein the improvementcomprises first and second thread-guiding elements between which is aspace in which an excess in length in the thread can hang down from thethread-guiding elements in the form of a loop, a baffle extendingdownward from the first and second thread-guiding elements, ad'acent andarallel to the loop of thread whic h hangs down rom such e ements, toshield t e loop against air currents, and a downward'directed nozzle,arranged adjacent to the first thread-guiding element, through which thethread enters the loop, for discharging fluid downward along thedescending leg of the loop in order to place the descending leg undertension so as to prevent the loop from tangling, the ascending leg ofthe loop being relatively free of tension.

2. A device according to claim 1, wherein the baffle is provided, alongits two vertical edges, with two sidewalls for confining and shieldingthe two legs of the loop.

3. A device for localizing an excess in length in a thread, adapted tobe interposed between a device for continuously supplying a thread and adevice for intermittently conveying the thread, wherein the improvementcomprises first and second thread-guiding elements, between which is aspace in which an excess in length in the thread can hang down from thethread-guiding elements in the form of a loop, and a downward-directednozzle, arranged adjacent to the first thread-guiding element, throughwhich the thread enters the loop, for discharging fluid downward alongthe descending leg of the loop in order to place the descending legunder tension so as to prevent the loop from tangling a seconddownwarddirected nozzle, the fluid discharging capacity of which issubstantially smaller than that of the first nozzle, arranged adjacentto the second thread-guiding element, for discharging fluid downwardalong the ascending leg of the loop, the ascending leg of the loop beingrelatively free of tension.

1. A device for localizing an excess in length in a thread, adapted tobe interposed between a device for continuously supplying a thread and adevice for intermittently conveying the thread, wherein the improvementcomprises first and second thread-guiding elements between which is aspace in which an excess in length in the thread can hang down from thethreadguiding elements in the form of a loop, a baffle extendingdownward from the first and second thread-guiding elements, adjacent andparallel to the loop of thread which hangs down from such elements, toshield the loop against air currents, and a downward-directed nozzle,arranged adjacent to the first threadguiding element, through which thethread enters the loop, for discharging fluid downward along thedescending leg of the loop in order to place the descending leg undertension so as to prevent the loop from tangling, the ascending leg ofthe loop being relatively free of tension.
 2. A device according toclaim 1, wherein the baffle is provided, along its two vertical edges,with two sidewalls for confining and shielding the two legs of the loop.3. A device for localizing an excess in length in a thread, adapted tobe interposed between a device for continuously supplying a thread and adevice for intermittently conveying the thread, wherein the improvementcomprises first and second thread-guiding elements, between which is aspace in which an excess in length in the thread can hang down from thethread-guiding elements in the form of a loop, and a downward-directednozzle, arranged adjacent to the first thread-guiding element, throughwhich the thread enters the loop, for discharging fluid downward alongthe descending leg of the loop in order to place the descending legunder tension so as to prevent the loop from tangling a seconddownward-directed nozzle, the fluid discharging capacity of which issubstantially smaller than that of the first nozzle, arranged adjacentto the second thread-guiding element, for discharging fluid downwardalong the ascending leg of the loop, the ascending leg of the loop beingrelatively free of tension.